Standard library header <any>

 

C++

Language

Standard library headers

Concepts

Utilities library

Strings library

Containers library

Algorithms library

Iterators library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

 

Standard Library header files

Language Support
<cstddef> <limits> <climits>	<cfloat> <cstdint> <new>	<typeinfo> <exception> <initializer_list>	<csignal> <csetjmp> <cstdarg>
Diagnostics
<stdexcept>	<cassert>	<cerrno>	<system_error>
General utilities
<utility> <memory> <memory_resource> <scoped_allocator>	<tuple> <optional> <any> <variant>	<bitset> <functional> <type_traits> <ratio>	<chrono> <ctime> <typeindex> <cstdlib>
Strings
<string> <string_view>	<cctype> <cwctype>	<cwchar> <cuchar>	<cstring>
Localization
<locale>	<codecvt>	<clocale>
Containers
<array> <deque> <vector>	<forward_list> <list>	<map> <set> <queue>	<unordered_map> <unordered_set> <stack>
Iterators
<iterator>
Algorithms
<algorithm>	<execution_policy>
Numerics
<complex> <random>	<valarray> <numeric>	<cfenv> <cmath>
Input/Output
<iosfwd> <iostream> <ios>	<streambuf> <istream> <ostream>	<iomanip> <sstream> <fstream>	<filesystem> <cstdio> <cinttypes>
Regular expressions
<regex>
Thread support
<thread> <atomic>	<mutex> <shared_mutex>	<condition_variable> <future>
C compatibility
<ciso646> <cstdalign>	<cstdbool> <ccomplex>	<ctgmath>

 

This header is part of the general utility library.

Classes

Name	Description
any (since C++17)	Objects that hold instances of any CopyConstructible type. (class)
bad_any_cast (C++17)	exception thrown by the value-returning forms of any_cast on a type mismatch (class)

Functions

std::swap(std::any) (C++17)	specializes the std::swap algorithm (function)
any_cast (C++17)	type-safe access to the contained object (function template)

Synopsis

namespace std {
  // class bad_any_cast
  class bad_any_cast;
  // class any
  class any;
  // non-member functions
  void swap(any& x, any& y) noexcept;
  template <class T, class... Args>
  any make_any(Args&& ...args);
  template <class T, class U, class... Args>
  any make_any(initializer_list<U> il, Args&& ...args);
  template<class ValueType>
  ValueType any_cast(const any& operand);
  template<class ValueType>
  ValueType any_cast(any& operand);
  template<class ValueType>
  ValueType any_cast(any&& operand);
  template<class ValueType>
  const ValueType* any_cast(const any* operand) noexcept;
  template<class ValueType>
  ValueType* any_cast(any* operand) noexcept;
}

Class std::bad_any_cast

class bad_any_cast : public bad_cast {
public:
  const char* what() const noexcept override;
};

Class std::any

class any {
public:
  // construction and destruction
  constexpr any() noexcept;
  any(const any& other);
  any(any&& other) noexcept;
  template <class ValueType> any(ValueType&& value);
  template <class ValueType, class... Args>
  explicit any(in_place_type_t<ValueType>, Args&&...);
  template <class ValueType, class U, class... Args>
  explicit any(in_place_type_t<ValueType>, initializer_list<U>, Args&&...);
  ~any();
  // assignments
  any& operator=(const any& rhs);
  any& operator=(any&& rhs) noexcept;
  template <class ValueType> any& operator=(ValueType&& rhs);
  // modifiers
  template <class ValueType, class... Args>
  void emplace(Args&& ...);
  template <class ValueType, class U, class... Args>
  void emplace(initializer_list<U>, Args&&...);
  void reset() noexcept;
  void swap(any& rhs) noexcept;
  // observers
  bool has_value() const noexcept;
  const type_info& type() const noexcept;
};